M R V C o m m u n i c a t i o n s , I n c . – I n s t a l l a t i o n M a n u a l
Indirect Chaining
Indirect Chaining is required for connecting FSO units not including clock recovery circuits. In cases of indirect connectivity, the connection between the two FSO units on the same roof must be done through the Switch or Router or another means of connection that is located inside the building. For example, in Fig. 2, we
A
C
Switch
B
use the indoor switch in building C for the chaining.
Fig. G.2
Indirect chaining
Direct Chaining
Direct Chaining is the capability to directly connect two FSO units on the same roof (used as repeaters ) i.e.. direct crossing between Rx and TX of the two units. For example, in Fig. 3 connection is achieved on rooftop of building C without the need to enter the building.
Direct connection is possible for FSO that include clock recovery circuits. The clock recovery regenerates the signal and enables smooth direct chaining.
ACB
Fig. G.3
Direct chaining
Chaining Limits
The number of links that can be chained is limited due to the Jitter parameter. Sensitivity to jitter is different for every protocol and can vary with different manufacturers. The typical number is
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